For respirating (also known as ventilating) a patient, above all for respiration at home, the breathing gas is humidified before it is fed to the patient. Room air is drawn in via a filter and fed to the patient via a humidifier in case of respiration at home, especially for the therapy of sleep apnea. Condensation may now occur in the interior space of the mask, which is perceived by the patient as disturbing if the patient must briefly remove the mask during the night to remove the condensate. Breathing masks that are worn by a patient during sleep are usually used in various positions, corresponding to the individual sleeping habits. High level of sleep comfort must be reached without the patient being disturbed by possible condensation.
A breathing mask in which a heating coil, which heats the mask to prevent condensation is arranged on the outside of the mask body, is known from JP 2002 052 082 A. The drawback of the prior-art mask is that an additional electric line must be led to the mask for operating the heating coil and that overheating of the mask may occur in case of a defect.